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user1874594
user1874594
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EXT4 partition on bad superblock . can this card be cleant

I have a 128gb micro sd formatted as ext4 10gb for app2sd 2nd ext4 partition ( p2 ) on my Android 6 phone . All my apps ( 80%) stay on that ext4 partition . Now app2sd cant load this partition - "unable to mount ....kgrinvalid file" Also the 119 gb main fat ( exFat ) partition ( p1) used to hold my data is mounted as RO. I am rooted on a Sony experia Z3

A brief background :
Was shooting a movie on my phone and it froze restarted twice . After that no luck mouting the ext4 partition.

Questions :

-- How can I get an fsck done on the ext4 file system and let the allocation table know there are bad blocks
-- Is there some mechanism inbuilt in the card that detects bad blocks and corruption and will put the card in RO mode for 1 partition and other partition ext4 cannot be mounted on phone
-- Some place I read this means the card is on its last legs and after some write cycles it becomes RO. Some tech support suggested this happend. I am not prepared to beleive . I ts only 4 months old bought from Amazon and I CAN write to it ( as will confirm ahead in the rest of the story )
-- I have ADB driver and get to # prompt on adb. I can possibly mount p1 as RW . I can confirm on adb that P2 is seen but it will not mount it
-- How can I get app2sd to mount this and be back in biz.

What I did

on live linux CD

-- I am able to mount both p1 and p2 as RW ( after explict command ) and only as Su. Normal user - its denied RO. SO on live ubuntu I CAN RW to both
-- Backed up P2 and then tried to DEL and format P2 ( gparted + fdisk manually ) - NO LUCK. Both give message its successful but after refresh they will show the SAME old partitions P1 and P2. Tried same on Window 7 - paragon partition manager - gives message its successful but after refresh they will show old configuration P1 and P2.
---Fsck 

it@it:~$ sudo fsck.ext4 -v /dev/sdc2
e2fsck 1.43.4 (31-Jan-2017)
app2sd: recovering journal
Superblock needs_recovery flag is clear, but journal has data.
Run journal anyway<y>? yes
fsck.ext4: unable to set superblock flags on app2sd


app2sd: ********** WARNING: Filesystem still has errors **********

-running the backup superblock fix does not help 

it@it:~$ sudo mke2fs -n  /dev/sdc2
mke2fs 1.43.4 (31-Jan-2017)
/dev/sdc2 contains a ext4 file system labelled 'app2sd'
    last mounted on /data/sdext2 on Sun Jan  7 07:21:35 2018
Proceed anyway? (y,N) y
Creating filesystem with 2604538 4k blocks and 651520 inodes
Filesystem UUID: 53138787-e743-4160-9041-ac9613d44db8
Superblock backups stored on blocks: 
    32768, 98304, 163840, 229376, 294912, 819200, 884736, 1605632

I tried various superblocks - NO LUCK .

I used this guide - NO LUCK
Superblock restore from backup

it@it:~$ sudo e2fsck -b   1605632 -B 4096 /dev/sdc2
e2fsck 1.43.4 (31-Jan-2017)
Superblock needs_recovery flag is clear, but journal has data.
Recovery flag not set in backup superblock, so running journal anyway.
app2sd: recovering journal
Superblock needs_recovery flag is clear, but journal has data.
Recovery flag not set in backup superblock, so running journal anyway.
Superblock needs_recovery flag is clear, but journal has data.
Recovery flag not set in backup superblock, so running journal anyway.
e2fsck: unable to set superblock flags on app2sd


app2sd: ***** FILE SYSTEM WAS MODIFIED *****

app2sd: ********** WARNING: Filesystem still has errors **********
user1874594
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